BoilerFaultCodesYour boiler is currently running a self-diagnostic check to ensure the ignition system is sparking correctly before it starts up.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Ignition test – checking the igniter spark
What causes this fault?
This is a brief, automated check that occurs when the boiler prepares to light the burner. It happens because the system's control board needs to verify that the ignition electrodes are capable of creating a spark before releasing gas. It is not an indication of a breakdown, but rather a standard safety protocol being carried out by the internal computer.
DIY fix possible
Wait for the test to complete automaticallyIf the code stays on screen for more than a few minutes, try restarting the boiler via the Reset button
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A boiler cover plan would cover faults like T1 — no call-out fees, no surprises.
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